If green is the new black, then water efficiency is the new green. As drought continues to plague areas of the country, water prices are trending upward, and municipalities clamp down on usage, the residential construction industry is finding ways to conserve this precious resource.

Shanahan’s HBA, along with the Green Builder Coalition, Build Green New Mexico and members of the city’s water conservation committee, has developed one solution: software that generates a Water Efficiency Rating Score, or WERS. The system is in the pilot testing phase.

Meanwhile, the Residential Energy Services Network, or RESNET — in partnership with the Natural Resources Defense Council and a coalition of stakeholders — is creating a Water Efficiency Rating, or WER Index.

Leaders of the two rating systems have been in talks about their respective projects.

Both water rating systems are cousins to RESNET’s Home Energy Rating System, or HERS Index, which rates a home based on its energy performance. The water ratings systems are designed to generate a score between zero and 100, with a lower number signifying a more water-efficient home.

Shanahan explained that the first version of WERS examines indoor water use, including the main plumbing fixtures of toilets, showers, kitchen sinks, and prime pumping— the amount of water that is wasted before usable hot water arrives at far away hot water fixtures. WERS also encourages innovative technologies such as rainwater catchment and greywater reuse, which can offset indoor water use or be credited to potential outdoor usage.

Developers are working to release the next WERS iteration, which will focus on outdoor use. Meanwhile RESNET expects to unveil its WER Index by the end of 2015.

Developers have turned to EPA’s WaterSense guidelines as a starting-off point, according to Jacob Atalla, co-chairman of a committee leading the effort and vice president of sustainability at KB Home.

“Now is the right time,” Atalla said. “People are very familiar with the HERS Index, so this is not a huge leap.”

Atalla hopes home builders can use the HERS and WER indices together to show consumers that their homes are built to be environmentally friendly — and can provide a good return on investment. When the index is complete, RESNET intends to submit the standard to the American National Standards Institute (ANSI) for approval. The ANSI certification means that the standard was developed through an open, consensus-based process.